A ligament is a piece of fibrous tissue which connects one bone to another within the body. Ligaments are frequently damaged (e.g., detached, torn or ruptured) as the result of injury or accident. A damaged ligament can impede proper stability and motion of a joint and cause significant pain. A damaged ligament can be replaced or repaired using various procedures, a choice of which can depend on the particular ligament to be restored and on the extent of the damage. When ligaments are damaged, surgical reconstruction can be necessary, as the ligaments may not regenerate on their own.
An example of a ligament that is frequently damaged as a result of injury, overexertion, aging and/or accident is the anterior cruciate ligament (ACL) that extends between a top of the tibia and a bottom of the femur. Another ligament that is often damaged and may need to be replaced is a posterior cruciate ligament (PCL). A damaged ACL or PCL can cause instability of the knee joint, arthritis, and substantial pain.
ACL reconstruction or repair typically includes the use of a tendon graft replacement procedure which usually involves drilling a bone tunnel through the tibia and up into the femur. Then a graft, which may be an artificial ligament or harvested graft, such as a tendon, is passed through a tibial portion of the tunnel (sometimes referred to as “the tibial tunnel”) across the interior of the joint, and up into a femoral portion of a tunnel (sometimes referred to as “the femoral tunnel”). One end of the ligament graft can then be secured in the femoral tunnel and another end of the graft is secured in the tibial tunnel, at the sites where the natural ligament attaches.
A number of conventional surgical procedures exist for re-attaching such ligament graft to bone, which have advantages and certain drawbacks. For example, a fixation device in the form of an elongate “button,” sometimes referred to as a “cortical button” can be used for an ACL fixation to the femur. However, such devices are relatively wide, such that it is required to remove a substantial amount of bone in the femur to drill a tunnel sized sufficiently to receive the device therethrough. This can complicate the surgery and extend its duration, as well as to cause inconvenience to the patient and delay healing.
Accordingly, there is a need for improved tissue fixation devices and techniques for using such devices.